While computers are still used for their traditional processing purposes, advances in communication infrastructures and protocols have turned standard computing devices into valuable communication tools. Computers communicate with each other, and with other electronic devices, over networks ranging from Local Area Networks (LANs) to wide reaching Global Area Networks (GANs) such as the Internet. Other electronic devices have experienced similar transformations, such as mobile phones, Personal Digital Assistants (PDAs), and the like. Today, these wireless devices are being used for a variety of different types of communication. For example, current and anticipated mobile phone technologies have transformed these wireless devices into powerful communication tools capable of communicating voice, data, images, video, and other multimedia content. PDAs, once the portable calendaring and organizational tool, now often include network communication capabilities such as e-mail, Internet access, etc. With the integration of wireless and landline network infrastructures, a multitude of new services are arising, and various information types can be conveniently communicated between wireless and/or landline terminals.
In many cases, new networks and network protocols are being developed to facilitate the new network services. For example, the Universal Mobile Telecommunications System (UMTS) represents an evolution from today's second generation (2G) mobile networks, and is a key concept in third generation (3G) mobile technologies. One particular protocol that may be used in connection with networks such as UMTS networks to provide various new services is the Session Initiation Protocol (SIP). SIP is an application-layer signaling protocol for creating, modifying, and terminating sessions with one or more participants. It can be used in applications such as Internet conferencing, telephony, presence, events notification, instant messaging, and the like.
In routing SIP messages through a UMTS or other SIP-enabled network, location services such as DNS or ENUM are typically using DNS or ENUM queries for obtaining the address of the next hop SIP server. This function is often implemented in the Serving-CSCF (S-CSCF) according to 3GPP terminology and specifications. Once-the message is forwarded to the next hop in the destination network, the message is sent to the Interrogating-CSCF (I-CSCF) that will take care of finding where the user is located within the local domain. However, SIP and other protocols may support multiple address schemes to be included in the messages, such as SIP, secure SIP, telephony, instant messaging, presence, etc. The determination of which hop is the next hop in the transmission of the message may be difficult, particularly where the location service provided multiple possible address schemes in response to a query, or where the location service fails to provide any useful response.
Accordingly, there is a need in the network communication industry for a manner of managing next hop addressing where multiple address schemes are provided in messages transmitted via a network. The present invention fulfills these and other needs, and offers other advantages over the prior art approaches.